Category Archives: "Tools"

I recently took the MIR Workshop at CCRMA Stanford (which I highly recommend) and got a chance to play around with python signal processing libraries including librosa. During the week one of the guest presenters used ‘Alphabet Aerobics’ by Blackalicious to demonstrate his source separation algorithm. This was a challenging piece of material because this track famously does not have a constant tempo and speeds up considerably throughout the song.

The thought struck me that it’d be way less interesting if the tempo was constant throughout, so this weekend I put my newly developed python processing skills to work and created ‘Boring Blackalicious’ – the constant tempo version of Alphabet Aerobics.

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It uses librosa’s onset detection, beat tracking and tempo estimation functions to create a tempo map (with the help of some manual tweaking to correct the estimated tempos of the later segments, where the librosa functions had more difficulty keeping up).

The tempo map was used to calculate the correct rate to slow down each segment using librosa’s phase vocoder function. I used the phase vocoder over librosa.effect.time_stretch so I could tweak the fft length directly to get a better sounding result.

One of the things that can really make your music stand out from the crowd and give it a professional sheen is high quality mastering. Mastering is a very different process from mixing which many amateur musicians who record their own tracks unfortunately often ignore. A fantastic place to start to learn about the art

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Dial-Up Modem? What the heck is that? Just kidding, of course – unless you were born in the late 90’s or later, you’ll be familiar with the sound of a dial-up modem handshake. This is the sequence of tones and noises that two remotely connected computers use to figure out each others capabilities to set

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Jukedeck are a UK based startup which is composed (ahem) of software developers, musicians and producers, who have developed a way to automatically generate music to suit any project. Their target is video producers, such as Youtube artists, that need royalty-free music to use without the pain of trawling through royalty-free libraries searching for a

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Sound Engineers and musicians will rejoice with the release of the SAFE project, or Semantic Audio Feature Extraction. The vague descriptions often used to get a particular sound in a mix, are being crowdsourced and applied to the set of VST plugins available for download from the SAFE project website. Users can download the plugin